2015 Chevrolet Tahoe steering problems

Tl* the contact called on behalf of her son who was the vehicle owner/driver of a 2015 chevrolet tahoe. While driving at approximately 45-50 MPH, the vehicle crashed into a tree. The contact was concerned that the collison may have been related to existing recalls on the vehicle. The driver was fatally injured. The contact was the mother of the driver. The contact stated that while her son was driving between 45-50 MPH, he lost control of the vehicle, jumping a curb, and crashed into a tree.

4th and most dangerous of 4 incidents in 3 weeks of ownership of 2015 chevy tahoe lt. Without driver instruction or interference the 2015 tahoe shifted itself into 4wd despite dial on 2wd. Steering difficult, car jerked, engine revved differently and trouble in reverse. No warning signals on display and I didn't know what was happening. Drove .5 mi., pulled over restarted, and then "4 wheel drive, dismiss" on display over steering wheel (no seat vibration, flashing lights as with lane drifting).